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/* ------------------------------------------------------------------------- */
/* */
/* i2c.h - definitions for the i2c-bus interface */
/* */
/* ------------------------------------------------------------------------- */
/* Copyright (C) 1995-2000 Simon G. Vogl
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
/* ------------------------------------------------------------------------- */
/* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> and
Frodo Looijaard <frodol@dds.nl> */
/* $Id: i2c.h,v 1.1 2003-05-22 10:25:25 giacomo Exp $ */
#ifndef I2C_H
#define I2C_H
#define I2C_DATE "20010830"
#define I2C_VERSION "2.6.1"
#include "drivers/i2c-id.h" /* id values of adapters et. al. */
#include <sys/types.h>
#include "drivers/compbttv.h"
struct i2c_msg;
/* --- General options ------------------------------------------------ */
#define I2C_ALGO_MAX 4 /* control memory consumption */
#define I2C_ADAP_MAX 16
#define I2C_DRIVER_MAX 16
#define I2C_CLIENT_MAX 32
#define I2C_DUMMY_MAX 4
struct i2c_algorithm;
struct i2c_adapter;
struct i2c_client;
struct i2c_driver;
struct i2c_client_address_data;
union i2c_smbus_data;
/*
* The master routines are the ones normally used to transmit data to devices
* on a bus (or read from them). Apart from two basic transfer functions to
* transmit one message at a time, a more complex version can be used to
* transmit an arbitrary number of messages without interruption.
*/
extern int i2c_master_send(struct i2c_client *,const char* ,int);
extern int i2c_master_recv(struct i2c_client *,char* ,int);
/* Transfer num messages.
*/
extern int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg msg[],int num);
/*
* Some adapter types (i.e. PCF 8584 based ones) may support slave behaviuor.
* This is not tested/implemented yet and will change in the future.
*/
extern int i2c_slave_send(struct i2c_client *,char*,int);
extern int i2c_slave_recv(struct i2c_client *,char*,int);
/* This is the very generalized SMBus access routine. You probably do not
want to use this, though; one of the functions below may be much easier,
and probably just as fast.
Note that we use i2c_adapter here, because you do not need a specific
smbus adapter to call this function. */
extern __s32 i2c_smbus_xfer (struct i2c_adapter * adapter, __u16 addr,
unsigned short flags,
char read_write, __u8 command, int size,
union i2c_smbus_data * data);
/* Now follow the 'nice' access routines. These also document the calling
conventions of smbus_access. */
extern __s32 i2c_smbus_write_quick(struct i2c_client * client, __u8 value);
extern __s32 i2c_smbus_read_byte(struct i2c_client * client);
extern __s32 i2c_smbus_write_byte(struct i2c_client * client, __u8 value);
extern __s32 i2c_smbus_read_byte_data(struct i2c_client * client, __u8 command);
extern __s32 i2c_smbus_write_byte_data(struct i2c_client * client,
__u8 command, __u8 value);
extern __s32 i2c_smbus_read_word_data(struct i2c_client * client, __u8 command);
extern __s32 i2c_smbus_write_word_data(struct i2c_client * client,
__u8 command, __u16 value);
extern __s32 i2c_smbus_process_call(struct i2c_client * client,
__u8 command, __u16 value);
/* Returns the number of read bytes */
extern __s32 i2c_smbus_read_block_data(struct i2c_client * client,
__u8 command, __u8 *values);
extern __s32 i2c_smbus_write_block_data(struct i2c_client * client,
__u8 command, __u8 length,
__u8 *values);
extern __s32 i2c_smbus_write_i2c_block_data(struct i2c_client * client,
__u8 command, __u8 length,
__u8 *values);
/*
* A driver is capable of handling one or more physical devices present on
* I2C adapters. This information is used to inform the driver of adapter
* events.
*/
struct i2c_driver {
char name[32];
int id;
unsigned int flags; /* div., see below */
/* Notifies the driver that a new bus has appeared. This routine
* can be used by the driver to test if the bus meets its conditions
* & seek for the presence of the chip(s) it supports. If found, it
* registers the client(s) that are on the bus to the i2c admin. via
* i2c_attach_client.
*/
int (*attach_adapter)(struct i2c_adapter *);
/* tells the driver that a client is about to be deleted & gives it
* the chance to remove its private data. Also, if the client struct
* has been dynamically allocated by the driver in the function above,
* it must be freed here.
*/
int (*detach_client)(struct i2c_client *);
/* a ioctl like command that can be used to perform specific functions
* with the device.
*/
int (*command)(struct i2c_client *client,unsigned int cmd, void *arg);
/* These two are mainly used for bookkeeping & dynamic unloading of
* kernel modules. inc_use tells the driver that a client is being
* used by another module & that it should increase its ref. counter.
* dec_use is the inverse operation.
* NB: Make sure you have no circular dependencies, or else you get a
* deadlock when trying to unload the modules.
* You should use the i2c_{inc,dec}_use_client functions instead of
* calling this function directly.
*/
void (*inc_use)(struct i2c_client *client);
void (*dec_use)(struct i2c_client *client);
};
/*
* i2c_client identifies a single device (i.e. chip) that is connected to an
* i2c bus. The behaviour is defined by the routines of the driver. This
* function is mainly used for lookup & other admin. functions.
*/
struct i2c_client {
char name[32];
int id;
unsigned int flags; /* div., see below */
unsigned int addr; /* chip address - NOTE: 7bit */
/* addresses are stored in the */
/* _LOWER_ 7 bits of this char */
/* addr: unsigned int to make lm_sensors i2c-isa adapter work
more cleanly. It does not take any more memory space, due to
alignment considerations */
struct i2c_adapter *adapter; /* the adapter we sit on */
struct i2c_driver *driver; /* and our access routines */
void *data; /* for the clients */
int usage_count; /* How many accesses currently */
/* to the client */
};
/*
* The following structs are for those who like to implement new bus drivers:
* i2c_algorithm is the interface to a class of hardware solutions which can
* be addressed using the same bus algorithms - i.e. bit-banging or the PCF8584
* to name two of the most common.
*/
struct i2c_algorithm {
char name[32]; /* textual description */
unsigned int id;
/* If an adapter algorithm can't to I2C-level access, set master_xfer
to NULL. If an adapter algorithm can do SMBus access, set
smbus_xfer. If set to NULL, the SMBus protocol is simulated
using common I2C messages */
int (*master_xfer)(struct i2c_adapter *adap,struct i2c_msg msgs[],
int num);
int (*smbus_xfer) (struct i2c_adapter *adap, __u16 addr,
unsigned short flags, char read_write,
__u8 command, int size, union i2c_smbus_data * data);
/* --- these optional/future use for some adapter types.*/
int (*slave_send)(struct i2c_adapter *,char*,int);
int (*slave_recv)(struct i2c_adapter *,char*,int);
/* --- ioctl like call to set div. parameters. */
int (*algo_control)(struct i2c_adapter *, unsigned int, unsigned long);
/* To determine what the adapter supports */
__u32 (*functionality) (struct i2c_adapter *);
};
/*
* i2c_adapter is the structure used to identify a physical i2c bus along
* with the access algorithms necessary to access it.
*/
struct i2c_adapter {
char name[32]; /* some useful name to identify the adapter */
unsigned int id;/* == is algo->id | hwdep.struct->id, */
/* for registered values see below */
struct i2c_algorithm *algo;/* the algorithm to access the bus */
void *algo_data;
/* --- These may be NULL, but should increase the module use count */
void (*inc_use)(struct i2c_adapter *);
void (*dec_use)(struct i2c_adapter *);
/* --- administration stuff. */
int (*client_register)(struct i2c_client *);
int (*client_unregister)(struct i2c_client *);
void *data; /* private data for the adapter */
/* some data fields that are used by all types */
/* these data fields are readonly to the public */
/* and can be set via the i2c_ioctl call */
/* data fields that are valid for all devices */
unsigned int flags;/* flags specifying div. data */
struct i2c_client *clients[I2C_CLIENT_MAX];
int client_count;
int timeout;
int retries;
};
/*flags for the driver struct: */
#define I2C_DF_NOTIFY 0x01 /* notify on bus (de/a)ttaches */
#define I2C_DF_DUMMY 0x02 /* do not connect any clients */
/*flags for the client struct: */
#define I2C_CLIENT_ALLOW_USE 0x01 /* Client allows access */
#define I2C_CLIENT_ALLOW_MULTIPLE_USE 0x02 /* Allow multiple access-locks */
/* on an i2c_client */
/* i2c_client_address_data is the struct for holding default client
* addresses for a driver and for the parameters supplied on the
* command line
*/
struct i2c_client_address_data {
unsigned short *normal_i2c;
unsigned short *normal_i2c_range;
unsigned short *probe;
unsigned short *probe_range;
unsigned short *ignore;
unsigned short *ignore_range;
unsigned short *force;
};
/* Internal numbers to terminate lists */
#define I2C_CLIENT_END 0xfffe
/* The numbers to use to set I2C bus address */
#define ANY_I2C_BUS 0xffff
/* The length of the option lists */
#define I2C_CLIENT_MAX_OPTS 48
/* ----- functions exported by i2c.o */
/* administration...
*/
extern int i2c_add_adapter(struct i2c_adapter *);
extern int i2c_del_adapter(struct i2c_adapter *);
extern int i2c_add_driver(struct i2c_driver *);
extern int i2c_del_driver(struct i2c_driver *);
extern int i2c_attach_client(struct i2c_client *);
extern int i2c_detach_client(struct i2c_client *);
/* Only call these if you grab a resource that makes unloading the
client and the adapter it is on completely impossible. Like when a
/proc directory is entered. */
extern void i2c_inc_use_client(struct i2c_client *);
extern void i2c_dec_use_client(struct i2c_client *);
/* New function: This is to get an i2c_client-struct for controlling the
client either by using i2c_control-function or having the
client-module export functions that can be used with the i2c_client
-struct. */
extern struct i2c_client *i2c_get_client(int driver_id, int adapter_id,
struct i2c_client *prev);
/* Should be used with new function
extern struct i2c_client *i2c_get_client(int,int,struct i2c_client *);
to make sure that client-struct is valid and that it is okay to access
the i2c-client.
returns -EACCES if client doesn't allow use (default)
returns -EBUSY if client doesn't allow multiple use (default) and
usage_count >0 */
extern int i2c_use_client(struct i2c_client *);
extern int i2c_release_client(struct i2c_client *);
/* returns -EBUSY if address has been taken, 0 if not. Note that the only
other place at which this is called is within i2c_attach_client; so
you can cheat by simply not registering. Not recommended, of course! */
extern int i2c_check_addr (struct i2c_adapter *adapter, int addr);
/* Detect function. It iterates over all possible addresses itself.
* It will only call found_proc if some client is connected at the
* specific address (unless a 'force' matched);
*/
typedef int i2c_client_found_addr_proc (struct i2c_adapter *adapter,
int addr, unsigned short flags,int kind);
extern int i2c_probe(struct i2c_adapter *adapter,
struct i2c_client_address_data *address_data,
i2c_client_found_addr_proc *found_proc);
/* An ioctl like call to set div. parameters of the adapter.
*/
extern int i2c_control(struct i2c_client *,unsigned int, unsigned long);
/* This call returns a unique low identifier for each registered adapter,
* or -1 if the adapter was not registered.
*/
extern int i2c_adapter_id(struct i2c_adapter *adap);
/* Return the functionality mask */
extern __u32 i2c_get_functionality (struct i2c_adapter *adap);
/* Return 1 if adapter supports everything we need, 0 if not. */
extern int i2c_check_functionality (struct i2c_adapter *adap, __u32 func);
/*
* I2C Message - used for pure i2c transaction, also from /dev interface
*/
struct i2c_msg {
__u16 addr; /* slave address */
unsigned short flags;
#define I2C_M_TEN 0x10 /* we have a ten bit chip address */
#define I2C_M_RD 0x01
#define I2C_M_NOSTART 0x4000
#define I2C_M_REV_DIR_ADDR 0x2000
short len; /* msg length */
char *buf; /* pointer to msg data */
};
/* To determine what functionality is present */
#define I2C_FUNC_I2C 0x00000001
#define I2C_FUNC_10BIT_ADDR 0x00000002
#define I2C_FUNC_PROTOCOL_MANGLING 0x00000004 /* I2C_M_{REV_DIR_ADDR,NOSTART} */
#define I2C_FUNC_SMBUS_QUICK 0x00010000
#define I2C_FUNC_SMBUS_READ_BYTE 0x00020000
#define I2C_FUNC_SMBUS_WRITE_BYTE 0x00040000
#define I2C_FUNC_SMBUS_READ_BYTE_DATA 0x00080000
#define I2C_FUNC_SMBUS_WRITE_BYTE_DATA 0x00100000
#define I2C_FUNC_SMBUS_READ_WORD_DATA 0x00200000
#define I2C_FUNC_SMBUS_WRITE_WORD_DATA 0x00400000
#define I2C_FUNC_SMBUS_PROC_CALL 0x00800000
#define I2C_FUNC_SMBUS_READ_BLOCK_DATA 0x01000000
#define I2C_FUNC_SMBUS_WRITE_BLOCK_DATA 0x02000000
#define I2C_FUNC_SMBUS_READ_I2C_BLOCK 0x04000000 /* New I2C-like block */
#define I2C_FUNC_SMBUS_WRITE_I2C_BLOCK 0x08000000 /* transfer */
#define I2C_FUNC_SMBUS_BYTE I2C_FUNC_SMBUS_READ_BYTE | \
I2C_FUNC_SMBUS_WRITE_BYTE
#define I2C_FUNC_SMBUS_BYTE_DATA I2C_FUNC_SMBUS_READ_BYTE_DATA | \
I2C_FUNC_SMBUS_WRITE_BYTE_DATA
#define I2C_FUNC_SMBUS_WORD_DATA I2C_FUNC_SMBUS_READ_WORD_DATA | \
I2C_FUNC_SMBUS_WRITE_WORD_DATA
#define I2C_FUNC_SMBUS_BLOCK_DATA I2C_FUNC_SMBUS_READ_BLOCK_DATA | \
I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
#define I2C_FUNC_SMBUS_I2C_BLOCK I2C_FUNC_SMBUS_READ_I2C_BLOCK | \
I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
#define I2C_FUNC_SMBUS_EMUL I2C_FUNC_SMBUS_QUICK | \
I2C_FUNC_SMBUS_BYTE | \
I2C_FUNC_SMBUS_BYTE_DATA | \
I2C_FUNC_SMBUS_WORD_DATA | \
I2C_FUNC_SMBUS_PROC_CALL | \
I2C_FUNC_SMBUS_WRITE_BLOCK_DATA
/*
* Data for SMBus Messages
*/
union i2c_smbus_data {
__u8 byte;
__u16 word;
__u8 block[33]; /* block[0] is used for length */
};
/* smbus_access read or write markers */
#define I2C_SMBUS_READ 1
#define I2C_SMBUS_WRITE 0
/* SMBus transaction types (size parameter in the above functions)
Note: these no longer correspond to the (arbitrary) PIIX4 internal codes! */
#define I2C_SMBUS_QUICK 0
#define I2C_SMBUS_BYTE 1
#define I2C_SMBUS_BYTE_DATA 2
#define I2C_SMBUS_WORD_DATA 3
#define I2C_SMBUS_PROC_CALL 4
#define I2C_SMBUS_BLOCK_DATA 5
#define I2C_SMBUS_I2C_BLOCK_DATA 6
/* ----- commands for the ioctl like i2c_command call:
* note that additional calls are defined in the algorithm and hw
* dependent layers - these can be listed here, or see the
* corresponding header files.
*/
/* -> bit-adapter specific ioctls */
#define I2C_RETRIES 0x0701 /* number of times a device address */
/* should be polled when not */
/* acknowledging */
#define I2C_TIMEOUT 0x0702 /* set timeout - call with int */
/* this is for i2c-dev.c */
#define I2C_SLAVE 0x0703 /* Change slave address */
/* Attn.: Slave address is 7 or 10 bits */
#define I2C_SLAVE_FORCE 0x0706 /* Change slave address */
/* Attn.: Slave address is 7 or 10 bits */
/* This changes the address, even if it */
/* is already taken! */
#define I2C_TENBIT 0x0704 /* 0 for 7 bit addrs, != 0 for 10 bit */
#define I2C_FUNCS 0x0705 /* Get the adapter functionality */
#define I2C_RDWR 0x0707 /* Combined R/W transfer (one stop only)*/
#if 0
#define I2C_ACK_TEST 0x0710 /* See if a slave is at a specific address */
#endif
#define I2C_SMBUS 0x0720 /* SMBus-level access */
/* ... algo-bit.c recognizes */
#define I2C_UDELAY 0x0705 /* set delay in microsecs between each */
/* written byte (except address) */
#define I2C_MDELAY 0x0706 /* millisec delay between written bytes */
/* ----- I2C-DEV: char device interface stuff ------------------------- */
#define I2C_MAJOR 89 /* Device major number */
# ifndef NULL
# define NULL ( (void *) 0 )
# endif
# ifndef ENODEV
# include <asm/errno.h>
# endif
/* These defines are used for probing i2c client addresses */
/* Default fill of many variables */
#define I2C_CLIENT_DEFAULTS {I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END, \
I2C_CLIENT_END, I2C_CLIENT_END, I2C_CLIENT_END}
/* This is ugly. We need to evaluate I2C_CLIENT_MAX_OPTS before it is
stringified */
#define I2C_CLIENT_MODPARM_AUX1(x) "1-" #x "h"
#define I2C_CLIENT_MODPARM_AUX(x) I2C_CLIENT_MODPARM_AUX1(x)
#define I2C_CLIENT_MODPARM I2C_CLIENT_MODPARM_AUX(I2C_CLIENT_MAX_OPTS)
/* I2C_CLIENT_MODULE_PARM creates a module parameter, and puts it in the
module header */
#define I2C_CLIENT_MODULE_PARM(var,desc) \
static unsigned short var[I2C_CLIENT_MAX_OPTS] = I2C_CLIENT_DEFAULTS; \
MODULE_PARM(var,I2C_CLIENT_MODPARM); \
MODULE_PARM_DESC(var,desc)
/* This is the one you want to use in your own modules */
#define I2C_CLIENT_INSMOD \
I2C_CLIENT_MODULE_PARM(probe, \
"List of adapter,address pairs to scan additionally"); \
I2C_CLIENT_MODULE_PARM(probe_range, \
"List of adapter,start-addr,end-addr triples to scan " \
"additionally"); \
I2C_CLIENT_MODULE_PARM(ignore, \
"List of adapter,address pairs not to scan"); \
I2C_CLIENT_MODULE_PARM(ignore_range, \
"List of adapter,start-addr,end-addr triples not to " \
"scan"); \
I2C_CLIENT_MODULE_PARM(force, \
"List of adapter,address pairs to boldly assume " \
"to be present"); \
static struct i2c_client_address_data addr_data = \
{normal_i2c, normal_i2c_range, \
probe, probe_range, \
ignore, ignore_range, \
force}
/* Detect whether we are on the isa bus. If this returns true, all i2c
access will fail! */
#define i2c_is_isa_client(clientptr) \
((clientptr)->adapter->algo->id == I2C_ALGO_ISA)
#define i2c_is_isa_adapter(adapptr) \
((adapptr)->algo->id == I2C_ALGO_ISA)
#endif /* I2C_H */